drivers/gpu/drm/i915/i915_gem_stolen.c

   1 /*
   2  * Copyright © 2008-2012 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *    Chris Wilson <chris@chris-wilson.co.uk>
  26  *
  27  */
  28
  29 #include <drm/drmP.h>
  30 #include <drm/i915_drm.h>
  31 #include "i915_drv.h"
  32
  33 /*
  34  * The BIOS typically reserves some of the system's memory for the exclusive
  35  * use of the integrated graphics. This memory is no longer available for
  36  * use by the OS and so the user finds that his system has less memory
  37  * available than he put in. We refer to this memory as stolen.
  38  *
  39  * The BIOS will allocate its framebuffer from the stolen memory. Our
  40  * goal is try to reuse that object for our own fbcon which must always
  41  * be available for panics. Anything else we can reuse the stolen memory
  42  * for is a boon.
  43  */
  44
  45 int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv,
  46                                 struct drm_mm_node *node, u64 size,
  47                                 unsigned alignment)
  48 {
  49         int ret;
  50
  51         if (!drm_mm_initialized(&dev_priv->mm.stolen))
  52                 return -ENODEV;
  53
  54         mutex_lock(&dev_priv->mm.stolen_lock);
  55         ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, size, alignment,
  56                                  DRM_MM_SEARCH_DEFAULT);
  57         mutex_unlock(&dev_priv->mm.stolen_lock);
  58
  59         return ret;
  60 }
  61
  62 void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
  63                                  struct drm_mm_node *node)
  64 {
  65         mutex_lock(&dev_priv->mm.stolen_lock);
  66         drm_mm_remove_node(node);
  67         mutex_unlock(&dev_priv->mm.stolen_lock);
  68 }
  69
  70 static unsigned long i915_stolen_to_physical(struct drm_device *dev)
  71 {
  72         struct drm_i915_private *dev_priv = dev->dev_private;
  73         struct resource *r;
  74         u32 base;
  75
  76         /* Almost universally we can find the Graphics Base of Stolen Memory
  77          * at offset 0x5c in the igfx configuration space. On a few (desktop)
  78          * machines this is also mirrored in the bridge device at different
  79          * locations, or in the MCHBAR. On gen2, the layout is again slightly
  80          * different with the Graphics Segment immediately following Top of
  81          * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
  82          * reported by 865g, so we just use the top of memory as determined
  83          * by the e820 probe.
  84          *
  85          * XXX However gen2 requires an unavailable symbol.
  86          */
  87         base = 0;
  88         if (INTEL_INFO(dev)->gen >= 3) {
  89                 /* Read Graphics Base of Stolen Memory directly */
  90                 pci_read_config_dword(dev->pdev, 0x5c, &base);
  91                 base &= ~((1<<20) - 1);
  92         } else { /* GEN2 */
  93 #if 0
  94                 /* Stolen is immediately above Top of Memory */
  95                 base = max_low_pfn_mapped << PAGE_SHIFT;
  96 #endif
  97         }
  98
  99         if (base == 0)
 100                 return 0;
 101
 102         /* make sure we don't clobber the GTT if it's within stolen memory */
 103         if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
 104                 struct {
 105                         u32 start, end;
 106                 } stolen[2] = {
 107                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
 108                         { .start = base, .end = base + dev_priv->gtt.stolen_size, },
 109                 };
 110                 u64 gtt_start, gtt_end;
 111
 112                 gtt_start = I915_READ(PGTBL_CTL);
 113                 if (IS_GEN4(dev))
 114                         gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
 115                                 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
 116                 else
 117                         gtt_start &= PGTBL_ADDRESS_LO_MASK;
 118                 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
 119
 120                 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
 121                         stolen[0].end = gtt_start;
 122                 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
 123                         stolen[1].start = gtt_end;
 124
 125                 /* pick the larger of the two chunks */
 126                 if (stolen[0].end - stolen[0].start >
 127                     stolen[1].end - stolen[1].start) {
 128                         base = stolen[0].start;
 129                         dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
 130                 } else {
 131                         base = stolen[1].start;
 132                         dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
 133                 }
 134
 135                 if (stolen[0].start != stolen[1].start ||
 136                     stolen[0].end != stolen[1].end) {
 137                         DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
 138                                       (unsigned long long) gtt_start,
 139                                       (unsigned long long) gtt_end - 1);
 140                         DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
 141                                       base, base + (u32) dev_priv->gtt.stolen_size - 1);
 142                 }
 143         }
 144
 145
 146         /* Verify that nothing else uses this physical address. Stolen
 147          * memory should be reserved by the BIOS and hidden from the
 148          * kernel. So if the region is already marked as busy, something
 149          * is seriously wrong.
 150          */
 151         r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
 152                                     "Graphics Stolen Memory");
 153         if (r == NULL) {
 154                 /*
 155                  * One more attempt but this time requesting region from
 156                  * base + 1, as we have seen that this resolves the region
 157                  * conflict with the PCI Bus.
 158                  * This is a BIOS w/a: Some BIOS wrap stolen in the root
 159                  * PCI bus, but have an off-by-one error. Hence retry the
 160                  * reservation starting from 1 instead of 0.
 161                  */
 162                 r = devm_request_mem_region(dev->dev, base + 1,
 163                                             dev_priv->gtt.stolen_size - 1,
 164                                             "Graphics Stolen Memory");
 165                 /*
 166                  * GEN3 firmware likes to smash pci bridges into the stolen
 167                  * range. Apparently this works.
 168                  */
 169                 if (r == NULL && !IS_GEN3(dev)) {
 170                         DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
 171                                   base, base + (uint32_t)dev_priv->gtt.stolen_size);
 172                         base = 0;
 173                 }
 174         }
 175
 176         return base;
 177 }
 178
 179 void i915_gem_cleanup_stolen(struct drm_device *dev)
 180 {
 181         struct drm_i915_private *dev_priv = dev->dev_private;
 182
 183         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 184                 return;
 185
 186         drm_mm_takedown(&dev_priv->mm.stolen);
 187 }
 188
 189 static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
 190                                      unsigned long *base, unsigned long *size)
 191 {
 192         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 193
 194         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 195
 196         switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
 197         case GEN6_STOLEN_RESERVED_1M:
 198                 *size = 1024 * 1024;
 199                 break;
 200         case GEN6_STOLEN_RESERVED_512K:
 201                 *size = 512 * 1024;
 202                 break;
 203         case GEN6_STOLEN_RESERVED_256K:
 204                 *size = 256 * 1024;
 205                 break;
 206         case GEN6_STOLEN_RESERVED_128K:
 207                 *size = 128 * 1024;
 208                 break;
 209         default:
 210                 *size = 1024 * 1024;
 211                 MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
 212         }
 213 }
 214
 215 static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
 216                                      unsigned long *base, unsigned long *size)
 217 {
 218         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 219
 220         *base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
 221
 222         switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
 223         case GEN7_STOLEN_RESERVED_1M:
 224                 *size = 1024 * 1024;
 225                 break;
 226         case GEN7_STOLEN_RESERVED_256K:
 227                 *size = 256 * 1024;
 228                 break;
 229         default:
 230                 *size = 1024 * 1024;
 231                 MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
 232         }
 233 }
 234
 235 static void gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
 236                                      unsigned long *base, unsigned long *size)
 237 {
 238         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 239
 240         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 241
 242         switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
 243         case GEN8_STOLEN_RESERVED_1M:
 244                 *size = 1024 * 1024;
 245                 break;
 246         case GEN8_STOLEN_RESERVED_2M:
 247                 *size = 2 * 1024 * 1024;
 248                 break;
 249         case GEN8_STOLEN_RESERVED_4M:
 250                 *size = 4 * 1024 * 1024;
 251                 break;
 252         case GEN8_STOLEN_RESERVED_8M:
 253                 *size = 8 * 1024 * 1024;
 254                 break;
 255         default:
 256                 *size = 8 * 1024 * 1024;
 257                 MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
 258         }
 259 }
 260
 261 static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
 262                                     unsigned long *base, unsigned long *size)
 263 {
 264         uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
 265         unsigned long stolen_top;
 266
 267         stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
 268
 269         *base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
 270
 271         /* On these platforms, the register doesn't have a size field, so the
 272          * size is the distance between the base and the top of the stolen
 273          * memory. We also have the genuine case where base is zero and there's
 274          * nothing reserved. */
 275         if (*base == 0)
 276                 *size = 0;
 277         else
 278                 *size = stolen_top - *base;
 279 }
 280
 281 int i915_gem_init_stolen(struct drm_device *dev)
 282 {
 283         struct drm_i915_private *dev_priv = dev->dev_private;
 284         unsigned long reserved_total, reserved_base = 0, reserved_size;
 285         unsigned long stolen_top;
 286
 287         mutex_init(&dev_priv->mm.stolen_lock);
 288
 289 #ifdef CONFIG_INTEL_IOMMU
 290         if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
 291                 DRM_INFO("DMAR active, disabling use of stolen memory\n");
 292                 return 0;
 293         }
 294 #endif
 295
 296         if (dev_priv->gtt.stolen_size == 0)
 297                 return 0;
 298
 299         dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
 300         if (dev_priv->mm.stolen_base == 0)
 301                 return 0;
 302
 303         stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
 304
 305         switch (INTEL_INFO(dev_priv)->gen) {
 306         case 2:
 307         case 3:
 308         case 4:
 309                 if (!IS_G4X(dev))
 310                         break;
 311                 /* fall through */
 312         case 5:
 313                 /* Assume the gen6 maximum for the older platforms. */
 314                 reserved_size = 1024 * 1024;
 315                 reserved_base = stolen_top - reserved_size;
 316                 break;
 317         case 6:
 318                 gen6_get_stolen_reserved(dev_priv, &reserved_base,
 319                                          &reserved_size);
 320                 break;
 321         case 7:
 322                 gen7_get_stolen_reserved(dev_priv, &reserved_base,
 323                                          &reserved_size);
 324                 break;
 325         default:
 326                 if (IS_BROADWELL(dev_priv) || IS_SKYLAKE(dev_priv))
 327                         bdw_get_stolen_reserved(dev_priv, &reserved_base,
 328                                                 &reserved_size);
 329                 else
 330                         gen8_get_stolen_reserved(dev_priv, &reserved_base,
 331                                                  &reserved_size);
 332                 break;
 333         }
 334
 335         /* It is possible for the reserved base to be zero, but the register
 336          * field for size doesn't have a zero option. */
 337         if (reserved_base == 0) {
 338                 reserved_size = 0;
 339                 reserved_base = stolen_top;
 340         }
 341
 342         if (reserved_base < dev_priv->mm.stolen_base ||
 343             reserved_base + reserved_size > stolen_top) {
 344                 DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
 345                               reserved_base, reserved_base + reserved_size,
 346                               dev_priv->mm.stolen_base, stolen_top);
 347                 return 0;
 348         }
 349
 350         /* It is possible for the reserved area to end before the end of stolen
 351          * memory, so just consider the start. */
 352         reserved_total = stolen_top - reserved_base;
 353
 354         DRM_DEBUG_KMS("Memory reserved for graphics device: %zuK, usable: %luK\n",
 355                       dev_priv->gtt.stolen_size >> 10,
 356                       (dev_priv->gtt.stolen_size - reserved_total) >> 10);
 357
 358         /* Basic memrange allocator for stolen space */
 359         drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
 360                     reserved_total);
 361
 362         return 0;
 363 }
 364
 365 static struct sg_table *
 366 i915_pages_create_for_stolen(struct drm_device *dev,
 367                              u32 offset, u32 size)
 368 {
 369         struct drm_i915_private *dev_priv = dev->dev_private;
 370         struct sg_table *st;
 371         struct scatterlist *sg;
 372
 373         DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
 374         BUG_ON(offset > dev_priv->gtt.stolen_size - size);
 375
 376         /* We hide that we have no struct page backing our stolen object
 377          * by wrapping the contiguous physical allocation with a fake
 378          * dma mapping in a single scatterlist.
 379          */
 380
 381         st = kmalloc(sizeof(*st), GFP_KERNEL);
 382         if (st == NULL)
 383                 return NULL;
 384
 385         if (sg_alloc_table(st, 1, GFP_KERNEL)) {
 386                 kfree(st);
 387                 return NULL;
 388         }
 389
 390         sg = st->sgl;
 391         sg->offset = 0;
 392         sg->length = size;
 393
 394         sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
 395         sg_dma_len(sg) = size;
 396
 397         return st;
 398 }
 399
 400 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
 401 {
 402         BUG();
 403         return -EINVAL;
 404 }
 405
 406 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
 407 {
 408         /* Should only be called during free */
 409         sg_free_table(obj->pages);
 410         kfree(obj->pages);
 411 }
 412
 413
 414 static void
 415 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
 416 {
 417         struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
 418
 419         if (obj->stolen) {
 420                 i915_gem_stolen_remove_node(dev_priv, obj->stolen);
 421                 kfree(obj->stolen);
 422                 obj->stolen = NULL;
 423         }
 424 }
 425 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
 426         .get_pages = i915_gem_object_get_pages_stolen,
 427         .put_pages = i915_gem_object_put_pages_stolen,
 428         .release = i915_gem_object_release_stolen,
 429 };
 430
 431 static struct drm_i915_gem_object *
 432 _i915_gem_object_create_stolen(struct drm_device *dev,
 433                                struct drm_mm_node *stolen)
 434 {
 435         struct drm_i915_gem_object *obj;
 436
 437         obj = i915_gem_object_alloc(dev);
 438         if (obj == NULL)
 439                 return NULL;
 440
 441         drm_gem_private_object_init(dev, &obj->base, stolen->size);
 442         i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 443
 444         obj->pages = i915_pages_create_for_stolen(dev,
 445                                                   stolen->start, stolen->size);
 446         if (obj->pages == NULL)
 447                 goto cleanup;
 448
 449         i915_gem_object_pin_pages(obj);
 450         obj->stolen = stolen;
 451
 452         obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
 453         obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 454
 455         return obj;
 456
 457 cleanup:
 458         i915_gem_object_free(obj);
 459         return NULL;
 460 }
 461
 462 struct drm_i915_gem_object *
 463 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 464 {
 465         struct drm_i915_private *dev_priv = dev->dev_private;
 466         struct drm_i915_gem_object *obj;
 467         struct drm_mm_node *stolen;
 468         int ret;
 469
 470         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 471                 return NULL;
 472
 473         DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
 474         if (size == 0)
 475                 return NULL;
 476
 477         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 478         if (!stolen)
 479                 return NULL;
 480
 481         ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
 482         if (ret) {
 483                 kfree(stolen);
 484                 return NULL;
 485         }
 486
 487         obj = _i915_gem_object_create_stolen(dev, stolen);
 488         if (obj)
 489                 return obj;
 490
 491         i915_gem_stolen_remove_node(dev_priv, stolen);
 492         kfree(stolen);
 493         return NULL;
 494 }
 495
 496 struct drm_i915_gem_object *
 497 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 498                                                u32 stolen_offset,
 499                                                u32 gtt_offset,
 500                                                u32 size)
 501 {
 502         struct drm_i915_private *dev_priv = dev->dev_private;
 503         struct i915_address_space *ggtt = &dev_priv->gtt.base;
 504         struct drm_i915_gem_object *obj;
 505         struct drm_mm_node *stolen;
 506         struct i915_vma *vma;
 507         int ret;
 508
 509         if (!drm_mm_initialized(&dev_priv->mm.stolen))
 510                 return NULL;
 511
 512         DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
 513                         stolen_offset, gtt_offset, size);
 514
 515         /* KISS and expect everything to be page-aligned */
 516         if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
 517             WARN_ON(stolen_offset & 4095))
 518                 return NULL;
 519
 520         stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 521         if (!stolen)
 522                 return NULL;
 523
 524         stolen->start = stolen_offset;
 525         stolen->size = size;
 526         mutex_lock(&dev_priv->mm.stolen_lock);
 527         ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
 528         mutex_unlock(&dev_priv->mm.stolen_lock);
 529         if (ret) {
 530                 DRM_DEBUG_KMS("failed to allocate stolen space\n");
 531                 kfree(stolen);
 532                 return NULL;
 533         }
 534
 535         obj = _i915_gem_object_create_stolen(dev, stolen);
 536         if (obj == NULL) {
 537                 DRM_DEBUG_KMS("failed to allocate stolen object\n");
 538                 i915_gem_stolen_remove_node(dev_priv, stolen);
 539                 kfree(stolen);
 540                 return NULL;
 541         }
 542
 543         /* Some objects just need physical mem from stolen space */
 544         if (gtt_offset == I915_GTT_OFFSET_NONE)
 545                 return obj;
 546
 547         vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
 548         if (IS_ERR(vma)) {
 549                 ret = PTR_ERR(vma);
 550                 goto err_out;
 551         }
 552
 553         /* To simplify the initialisation sequence between KMS and GTT,
 554          * we allow construction of the stolen object prior to
 555          * setting up the GTT space. The actual reservation will occur
 556          * later.
 557          */
 558         vma->node.start = gtt_offset;
 559         vma->node.size = size;
 560         if (drm_mm_initialized(&ggtt->mm)) {
 561                 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
 562                 if (ret) {
 563                         DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
 564                         goto err_vma;
 565                 }
 566         }
 567
 568         vma->bound |= GLOBAL_BIND;
 569
 570         list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
 571         list_add_tail(&vma->mm_list, &ggtt->inactive_list);
 572         i915_gem_object_pin_pages(obj);
 573
 574         return obj;
 575
 576 err_vma:
 577         i915_gem_vma_destroy(vma);
 578 err_out:
 579         i915_gem_stolen_remove_node(dev_priv, stolen);
 580         kfree(stolen);
 581         drm_gem_object_unreference(&obj->base);
 582         return NULL;
 583 }